WM8903
Production Data
DIGITAL MICROPHONE INTERFACE .......................................................................... 40
ANALOGUE-TO-DIGITAL CONVERTER (ADC) ............................................................ 42
ADC DIGITAL VOLUME CONTROL ................................................................................................................................ 42
HIGH-PASS FILTER (HPF) ............................................................................................................................................. 45
ADC OVERSAMPLING RATIO (OSR) ............................................................................................................................ 46
DYNAMIC RANGE CONTROL (DRC) ........................................................................... 46
COMPRESSION/LIMITING CAPABILITIES .................................................................................................................... 46
GAIN LIMITS.................................................................................................................................................................... 48
DYNAMIC CHARACTERISTICS ..................................................................................................................................... 49
ANTI-CLIP CONTROL ..................................................................................................................................................... 50
QUICK RELEASE CONTROL ......................................................................................................................................... 50
GAIN SMOOTHING ......................................................................................................................................................... 51
INITIALISATION .............................................................................................................................................................. 52
DIGITAL MIXING ............................................................................................................ 53
DIGITAL MIXING PATHS ................................................................................................................................................ 53
DAC INTERFACE VOLUME BOOST .............................................................................................................................. 54
DIGITAL SIDETONE........................................................................................................................................................ 55
DIGITAL-TO-ANALOGUE CONVERTER (DAC) ............................................................ 56
DAC DIGITAL VOLUME CONTROL ................................................................................................................................ 57
DAC SOFT MUTE AND SOFT UN-MUTE ....................................................................................................................... 59
DAC MONO MIX .............................................................................................................................................................. 60
DAC DE-EMPHASIS........................................................................................................................................................ 60
DAC SLOPING STOPBAND FILTER .............................................................................................................................. 61
DAC BIAS CONTROL...................................................................................................................................................... 61
DAC OVERSAMPLING RATIO (OSR) ............................................................................................................................ 62
OUTPUT SIGNAL PATH ................................................................................................ 63
OUTPUT SIGNAL PATHS ENABLE ................................................................................................................................ 64
HEADPHONE / LINE OUTPUT SIGNAL PATHS ENABLE ............................................................................................. 65
OUTPUT PGA BIAS CONTROL ...................................................................................................................................... 68
OUTPUT DRIVERS BIAS CONTROL ............................................................................................................................. 68
OUTPUT MIXER CONTROL ........................................................................................................................................... 69
OUTPUT VOLUME CONTROL ....................................................................................................................................... 71
ANALOGUE OUTPUTS ................................................................................................. 75
HEADPHONE OUTPUTS – HPOUTL AND HPOUTR ..................................................................................................... 75
LINE OUTPUTS – LINEOUTL AND LINEOUTR ............................................................................................................. 75
DIFFERENTIAL LINE OUTPUTS – LON/LOP AND RON/ROP ...................................................................................... 75
EXTERNAL COMPONENTS FOR GROUND-REFERENCED OUTPUTS...................................................................... 76
REFERENCE VOLTAGES AND MASTER BIAS ........................................................... 77
POP SUPPRESSION CONTROL .................................................................................. 79
DISABLED INPUT / OUTPUT CONTROL ....................................................................................................................... 79
DIFFERENTIAL LINE OUTPUT DISCHARGE CONTROL .............................................................................................. 79
CHARGE PUMP ............................................................................................................. 80
DC SERVO ..................................................................................................................... 81
DIGITAL AUDIO INTERFACE ........................................................................................ 84
MASTER AND SLAVE MODE OPERATION ................................................................................................................... 84
OPERATION WITH TDM ................................................................................................................................................. 85
BCLK FREQUENCY ........................................................................................................................................................ 86
AUDIO DATA FORMATS (NORMAL MODE) .................................................................................................................. 86
AUDIO DATA FORMATS (TDM MODE) ......................................................................................................................... 88
DIGITAL AUDIO INTERFACE CONTROL ..................................................................... 90
BCLK AND LRCLK CONTROL ........................................................................................................................................ 91
COMPANDING ................................................................................................................................................................ 93
LOOPBACK ..................................................................................................................................................................... 94
MICROPHONE HOOK SWITCH DETECTION ................................................................................................................ 39
w
PD, Rev 4.5, June 2012
4
WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
